Air-gap filter

ABSTRACT

Disclosed is an air-gap filter. In certain embodiments, the air gap filter comprises a body having an inner surface, and an outer surface; an upper rim disposed on an end of the body; a lower portion disposed on an end of the body, opposite the upper rim, said lower portion defining a plurality of openings; and an inlet tube cutout defined by the outer surface of the body. The air-gap filter may be composed of metal alloys, plastics, or composite materials. Also disclosed are various embodiments of air-gaps that include an air-gap filter.

PRIORITY CLAIM

This application claims the benefit of U.S. Provisional Application 62/023,880 filed on Jul. 13, 2014. This application is incorporated herein by reference.

BACKGROUND

Present air gaps fail to prevent waste objects from transferring from the inlet to outlet tubes. Embodiments of the disclosed invention provide numerous advantages over existing air gaps. Specifically, the disclosed invention impedes the flow of waste objects from the inlet to outlet tube. Additionally, in certain embodiments, the air gap filter can be located in a location amenable to easy cleaning. Certain embodiments are fully backward and forward compatible with multiple air gaps. Backwards and forward compatibility is realized by matching pipe diameters and length. Finally, the disclosed air gap filter may be composed of materials having properties specific to its intended use. In certain embodiments, the air gap filter may be composed of a soft material in applications in which it would be desirable for the air gap filter to be ground by a disposer. In other embodiments, where the air gap filter is intended to have a long life, the air gap filter may be composed of a hard material.

BRIEF SUMMARY

Disclosed is an air-gap filter. In certain embodiments, the air gap filter comprises a body having an inner surface, and an outer surface; an upper rim disposed on an end of the body; a lower portion disposed on an end of the body, opposite the upper rim, said lower portion defining a plurality of openings; and an inlet tube cutout defined by the outer surface of the body. In certain embodiments, the air-gap filter surrounds an inlet tube in an air-gap. The air-gap filter may be composed of metal alloys, plastics, or composite materials. In certain embodiments, a positive stop is disposed on the upper rim of the air-gap filter.

FIGURES

FIG. 1 is an illustration of an isometric-type and sectional view of an embodiment of a filter.

FIG. 2 is an illustration of an embodiment of a sink assembly having an air gap fixture.

FIG. 3 is an illustration of an embodiment of a dishwasher air-gap.

FIG. 4 is an illustration of an embodiment of an assembly of a “screw type” air-gap.

FIG. 5 is an illustration of an embodiment of an assembly of a “snap type” air-gap.

FIG. 6 is an illustration of a representative flow path in an embodiment of an air-gap.

FIG. 7 illustrates multiple views of one embodiment of an air gap filter.

FIG. 8 is an illustration of an embodiment of an air gap assembly with an invented filter installed.

FIG. 9 illustrates a sectional view of and air gap filter.

FIG. 10 illustrates an embodiment of an air-gap filter having a positive stop disposed on the upper rim.

DETAILED DESCRIPTION

FIG. 1 shows an isometric-type and sectional view of an embodiment of an air-gap filter. All the surfaces and features are explained by FIGS. 7 and 9 and their related descriptions. In certain embodiments, the air-gap filter may be composed of metal alloys, composite materials, plastics, polymers, or any other suitable material.

FIG. 2 shows an embodiment of a sink layout as it relates to a dishwasher air-gap. Preventing dishwasher air-gap drain path blockages is an objective of the filter disclosed herein. In certain embodiments, a dishwasher discharge hose 44 forces waste water into an inlet 34. Inlet 34 in turn directs water into an air-gap body 60 that takes the water above a counter 22. Directing water above the counter allows water to be redirected under a protective cap 200 and into a sink 24 if the water drain path is blocked. During normal operation waste water is redirected through the air gap fixture 20 into outlet 38. From outlet 38 water flows to disposer inlet 42, through a disposer 26, water continues out through an elbow 28 into a trap 30 and finally out through another elbow 32 into the sewer system. Air gaps can also be located under counter top 22.

FIG. 3 is a more detailed view of an embodiment of an air-gap. Here again inlet 34 is visible with its external barbs 96 used to secure hoses. Hoses are sometimes secured to Air-gaps using friction generated by hose barbs 90 and 96 or via compression from a hose clamp or related device (not shown), or a combination of both. Also, the external drain outlet 38 is visible with its external barbs 90. Note the outlet is usually larger because it is gravity fed and not force fed waste water. This view shows mounting nuts 66 and 68 that thread onto an enlarged externally threaded portion 62 and together with mounting gasket seals 70 fix air-gap body 60 to the counter 22. The last two features in FIG. 3 are air vent openings 78 and deflector 84. Air vent openings allow air to enter the outlet line, prevent vacuums, break backflow and provide an outlet in case drain line 38 gets blocked. Deflector 84 prevents forced waste water from inlet 34 from creating a fountain and flooding counter top 22.

FIG. 4 shows an assembly that makes up one type of air gap. This type of air-gap will be called a screw type because a defector 84, which includes occluded inner threads 77, is screwed onto the upper portion of a chamber wall 74, which has external threads 75. Chamber wall 74, which has occluded inner threads 81, mounts onto air gap body 60 via air gap body external threads 79. Chamber wall 74 includes a mounting nut 68, which usually establishes the vertical position of the assembly. Mounting nut 68, with the help of mounting gasket seal 70 and threads on the lower portion of chamber wall 74, provide features to secure the air-gap fixture to a sink. As mentioned, water normally flows from inlet 34 through inlet tube spout 300 then out outlet 38.

FIG. 5 shows an assembly that makes up one type of air-gap. This type of air-gap will be called a snap type because deflector 400 has a snap feature 300 that snaps into vents 204. In certain embodiments, one snap feature may exist, while in others, a plurality of snap features may be present. This snap feature 300 is similar to those disposed on phone or Ethernet cables because during installation snap 300 is wedged between the air gap and deflector until it aligns with vent “window” 204 at which time it expands and is secured. To remove deflector 400, one depresses snaps 300 and slides the deflector 400 up and out of the air gap, in much the same way the snap of a phone or Ethernet cable is pressed then pulled. Here mounting nuts 68 and mounting gaskets 70 secure the air-gap body 60 to a sink. As mentioned, water nominally flows from inlet 34, through inlet tube spout 300 then out outlet 38. The vent redirects water flowing backwards through a similar feature in protective cap 200, shown in FIG. 2, etc.

FIG. 6 shows the typical flow path of waste water F, under protective cap 200, and how, in the absence of a filter, the waste water is not strained, which may lead to a back-up of wastewater.

FIG. 7 includes layouts of one embodiment of a filter. The air-gap filter comprises an inner surface 215, an outer surface 216, a lower portion 217, and an upper rim 218. In one embodiment, the body 102 attaches to existing air-gaps via the inlet tube cutout 104 by wrapping around inlet tube 300 (shown previously). The inlet tube cutout is defined by the outer surface of the body 102. The filter's position can be constrained inside the outlet tube via some contact friction. In certain embodiments a positive stop feature, such as 106, prevents over insertion. Positive stop features can be disposed on, over, under or affixed to various parts of the filter. In certain embodiments, the positive stop extends circumferentially around the upper rim 218. In other embodiments, the positive stop feature extends from the upper rim 218 into the inlet tube cutout 104. When installed, waste water is filtered through filter drain openings 108. The lower portion 217, defines a plurality of openings 108. These openings 108 function as a filter mechanism. Careful calculations are required to determine appropriate filter drain opening 108 area to ensure mass flow rate of water is balanced. By way of example, a representative calculation is as follows: the inlet tube has a given area, therefore the upper portion of the filter (here the crescent part) must have an area equal or greater than the inlet area, similarly the sum of areas of the lower portion of the filter (here the openings) must also have an area equal or greater than the inlet area. In certain embodiments, a filter removal rim/lip 110 is included as part of the filter to facilitate removal. This rim/lip provides a positive locating feature to pull on much in the same way a glass beer/soda bottle cap has a rim/lip to receive bottle openers.

FIG. 8 shows the air-gap assembly with the air-gap filter installed. In one filter embodiment, the filter body 102 is secured by wrapping around the inlet tube spout 300. Certain features of one embodiment of the filter include the filter body 102, the inlet tube cut out 104, the positive stop 106, the filter drain openings 108 and removal rim/lip 110. Removal rim/lip 110 is explained in more detail in FIG. 9.

FIG. 9 exists to show one embodiment of the filter removal rim/lip 110 in greater detail. Both the positive stop 106 and the removal rim/lip 110 provide resisting surfaces that can be used for removing filter body 102 with a finger or an appropriate tool.

FIG. 10 illustrates and embodiment of an air-gap filter wherein a positive stop disposed circumferentially, and extending from the upper rim 218 of the air gap filter. In such embodiments, the positive stop may not extend into the inlet tube cutout 104.

As illustrated in FIG. 2, it is very cumbersome to clean the hose that connects air-gap outlet 38 to disposer inlet 42. The included figures show one way to reconfigure air-gaps and filter all the waste water. Users first remove protective cap 200 and deflector 84 or 400 from air-gap fixture 20 then insert the invented filter around inlet tube spout 300. After this users reassemble the deflector by screwing cap 84 or snapping deflector 400 back in place. Finally, the protective cap 200 is pressed over the whole assembly; it is recommended to have vent 78 facing the sink basin 24. The cleaning procedure follows the steps above. Also the cleaning procedure requires no special tools or plumbing knowledge.

Air-gap filters for wastewater can be designed for dishwashers and other appliances producing wastewater. Many embodiments can be utilized to attain specific results for unique situations. For example, different materials, sizes, and connectors can be used for all components. Additionally, the positive stop feature can exist in several geometric forms, for example, grabbing inside or outside, using friction or other means for attachment. Finally, the filter can be part of the original air gap assembly or it may exist as one or more pieces sold individually and installed after factory production of the air gap.

While the invention has been described and illustrated with reference to certain particular embodiments thereof, those skilled in the art will appreciate that the various adaptations, changes, modifications, substitutions, deletions, or additions or procedures and protocols may be made without departing from the spirit and scope of the invention. It is intended, therefore, that the invention be defined by the scope of the claims that follow and that such claims be interpreted as broadly as reasonable. 

What is claimed is:
 1. An air-gap filter comprising: a body having an inner surface, and an outer surface; an upper rim disposed on an end of the body; a lower portion disposed on an end of the body, opposite the upper rim, said lower portion defining a plurality of openings; and an inlet tube cutout defined by the outer surface of the body.
 2. The air-gap filter of claim 1 wherein the air-gap filter is composed of one or more materials selected from the group consisting of: metal alloy plastic; and composite materials.
 3. The air-gap filter of claim 2 wherein the air-gap filter further comprises a positive stop.
 4. The air-gap filter of claim 3 wherein the positive stop extends outward from the upper rim, into the inlet tube cutout defined by the outer surface of the cylindrical body.
 5. The air-gap filter of claim 3 wherein the positive stop extends outward from the upper rim circumferentially, not extending into the inlet tube cutout.
 6. An air-gap assembly comprising: an inlet tube; and an air-gap filter comprising: a body having an inner surface, and an outer surface; an upper rim disposed on an end of the body; a lower portion disposed on an end of the body, opposite the upper rim, said lower portion defining a plurality of openings; and an inlet tube cutout defined by the outer surface of the body; wherein the inlet tube is situated within the inlet tube cutout defined by the outer surface of the body.
 7. The air-gap assembly of claim 6 further wherein the air-gap filter is composed of one or more materials selected from the group consisting of: metal alloy plastic; and composite materials.
 8. The air-gap assembly of claim 7 further comprising: a deflector disposed on a wall of the air gap assembly; and a snap disposed on the deflector.
 9. The air-gap assembly of claim 7 further comprising: a deflector having occluded inner threads; and a chamber wall having external threads; wherein the deflector is screwed into the chamber wall. 